Engine-starter.



-V. BENDIX,

' ENGINE STARTER.

Amlcmog men Aue.-z6. 1916.

1,258,303. Patented Mar. 5,1918.

VINCENT BENIJIX, or CHICAGO, ILLINOIS.

ENGINE-STARTER.

Specification of Letters Patent;

Patented Mar. 5, 1918.

Application filed August 26, 1916. Serial No. 117,093.

To all whom it may concern:

Be it known that I, VINCENT BENDIX, a citizen of the United States, residing at Ohicago, in the county of Cook and State of inois, have invented certain new and useful Improvements in Engine-Starters, of-

which the following is a specification.

My invention relates to that type of engine starter exemplified in patents heretofore issued to me, for instance, Patent No. 1,172,864, dated February 22, 1916, and Patent N 0. 1,146,992, dated July 20, 1915, which starter is characterized bya prime mover,

such as an electric motor, and a transmission or drive for transmitting the power of the motor by means of a screw shaft and pinion mounted thereon to a member of the engine to be started, such as the fly wheel thereof. This drive comprises a screw shaft, operating either directly or indirectly by the motor and a pinion screwthreaded on such shaft having longitudinal movement thereon and rotary movement therewith. My invention pertains to the construction and formation of the teeth of this pinion at the meshing end thereof, and the object thereof is to so construct such pinion teeth as to improve the meshing action thereof and prevent wear and injury on such teeth as well as on the teeth of the flywheel or other engine member.

In the drawing, Figure 1 is an elevation of a portion of the drive illustrating a pinion embodying my invention, and also showing a portion of a fly wheel, partly in section, with which the pinion meshes; Figs. 2 and 3 are detail perspective views of the end of one of the teeth of the pinion; Fig, 4 a plan view of one of the pinion teeth; and Fig. 5 an end view of portion of the fly wheel gear. 7

As shown in Fig. 1, the portionof the drive herein illustrated comprises the screwshaft 1, pinion 2 screw-threaded thereupon and the stop-nut 3 at one-end of the screwshaft. When the screw-shaft is rotated by the motor (not shown) the to move to the right longitudinally of the shaft and to mesh with the teeth of the fly wheel 4, or other rotary engine member.

In the meshing operation the pinion is not pinion 2 will inion is adapted always presented to the fly-wheel teeth in accurate meshing position, that is, with-the teeth of the with the of the of the end ance or stoppage of the longitudinal movement of the pinion will compel a longitudi nal or'endwise movement of the screw-shaft agamst the tension of the coiled spring and a slight rotary movement vof the pinion on the screw-shaft until the proper alinement or register occurs between the pinion and the fly-wheel teeth. 4 Also it sometimes happens that this lack of reg'i'stenbetween the teeth for proper meshing operation is only partial, and in such event,'a partial rotation of the pinion in the manner described will bring about the proper register and the consequent final meshing between the pinion and the fly-wheel.

pinion in alinement or register to end. In such latter case the resist The object of my invention is to facilitate this meshing operation, and to prevent; possible injury to the meshing parts, by beveling or chamfering ,one side only of the teeth at the meshing ing and rounding the extreme ends thereof. The chamfering of the teeth is on that side opposite the driving side of the teeth when they are in mesh with the fly-wheel, or in other words, the righthand side of the teeth when they are viewed fromthe left hand side of Fig. 1, it being understood that the electric motor drives the shaft in an anticlockwise direction when viewed from the left in-Fig. 1, with the result that the rotate in the same direction when it has slight partial rotationof the pinion which end thereof, and also curvoccurs when the pinion is stopped momentarily intits longitudinal movement by the fa lure of the same to register accurately with the fly-wheel. The chamferingon V of the fly-wheel teeth, thereby facilitating. the

rotary. movement of the .p1n1on for proper r this particular sideof the pinion teeth has, a-

rotameshing. If both sides of the pinion teeth should be thus chamfered, there would be some occasions when the chamfering on that side of the teeth which are straight or unchamfered in the present instance would have atendency to rotate the pinion slightly in the reversed direction, that is, contrary to its normal and proper direction of rotation,

and as a stoppage of the-pinion causesthe screw-shaft to rotate the pimon in unison therewith, the result would be a greater pressure brought upon the engaging portions of the teeth of the pinion and the, fiy-wheel.

As clearly shown, in the drawing, the teeth 2 of the pinion have a chamfer 2 on one side, the other side being substantially wheel teeth. It is obviousthat in case the register between the teeth of the pinion and fiy-wheel is only partial, the end of the teeth 7 of the pinion will strike and bear along one side of the fly-wheel teeth. "This described formation of the end of the pinion teeth will prevent any wedging and binding action of the engaging teeth, and any abrasion or chiseling of the fly-wheel teeth, thereby permitting the engaging surfaces to move smoothly and without. injury upon each other. L

This peculiar formation or chamfermg of the engaging ends of the pinion teeth assisted by the yielding longitudinal movement of the screw-shaft permits of the use of unchamfered teeth on the fly-wheel and permits of the use of cast iron fly wheels which are more economical. As shown by Figs. 1 and 5, the engaged ends of the flywheel teeth are flat, that is unchamfered, and the construction of the parts is such that the pinion will readily and properly mesh with the fiy-Wheel gear even when there is an initial contact of'the teeth end to end, the longitudinal yielding movement of the shaft assisting in the meshing operation under such conditions inasmuch as the pinion starts its meshing operation during chaimfered ends being curved.

2. In an engine starter transmission or only the side opposite its driving side, such drive, the combination of a rotatable member, and a pinion. actuated thereby to move longitudinally thereof into engagement with a wheel of the engine to be started, and rotarily therewith, the teeth of the pinion being chamfered at their engaging end and on only the side opposite its driving side, such chamfered ends being straight substantially to a point corresponding with the pitch line p and curvedtherebeyond.

3. In an engine starter transmission or drive, the combination of a rotatable member, and a pinion actuated thereby to move longitudinally thereof into engagement with a wheel of the engine to be started, and r0- tarily therewith, the teeth of the pinion be ing chamfered at their engaging end and on only the side opposite its driving side,

the extreme chamfered ends of such teeth being rounded. 1

4:. In an engine starter transmission or drive, the combination of; a rotatable member, and a pinion actuated thereby to move longitudinally thereof into engagement with a wheel of the engine to be started, and rotarily therewith, the teeth of the pinion being chamfered at their engaging end and on only the side opposite its driving side, such chamfered ends being straight substantially to a point corresponding with the pitch line and curved therebeyond, and such .ends being also rounded.

5. In an engine starter transmission or drive, the combination of a rotatable member, and a pinion actuated thereby to move longitudinally thereof into engagement with a wheel of the engine to be started, and rotarily therewith, the teeth of the pinion being chamfered at their engaging end and on only the side opposite its driving side, such chamfered ends being straight substantially to a point corresponding with the pitch line and curved. 'therebeyond, and the corners of such ends of the teeth being rounded with a somewhat blunt portion intervening.

6. In an engine starter transmission or drive, the combination of a gear connected with the engine to be started having teeth with unchamfered ends, a rotatable member, and a pinion actuated thereby to move longitudinally thereof into engagement with said gear and rotarily with such shaft, teeth of the pinion being chamfered at their en-- drivingslde. 7. In an engine starter transmission or gaging end and on only the side opposite its drive, the combination of a rotatable memher, and a pinion actuated thereby to move longitudinally thereof into engagement with a wheel of the engine to be started, and rotarily therewith, the teeth of the-pinion being chamfered at their engaging end and on only the side Opposite its driving side, said screw-shaft having a yielding endwise movement when the pinion teeth contact with said Wheel;

VINCENT BENDIX. v

Witnesses:

S. E. HIB EN, ROBERT DOBBERMAN. 

